The present invention relates to bromine-containing polymers and to a process of preparing these bromine-containing polymers.
In all kind of plastics applications, the plastics used are often required to have flame-retarding properties. This applies in particular where plastics are used in articles such as domestic appliances, in the automotive industry, and where plastics are used as building materials.
The usual method by which flame-retarding properties are imparted to the plastics is the blending-in of flame retardants and most of these flame retardants contain bromine, for example brominated diphenyl or diphenyloxide compounds. Together with antimony trioxide these flame retardants impart good flame-retarding properties to the plastics when included in the plastics mixture by blending.
However, these flame retardants have a major disadvantage in that the incorporation of these flame retardants and the processing of the plastics incorporating brominated flame retardants gives rise to problems and specifically that the flame retardant or decomposition products thereof may be released. The can cause an offensive odor and, in addition, it is possible in certain cases for noxious compounds to be released. In addition, these included flame retardants considerably affect the mechanical properties of the plastics in which they are contained.
Many proposals have been made to overcome such difficulties. A large number of proposals simply amount to the replacement of the brominated compounds with compounds containing nitrogen and/or phosphorus which are similarly blended in the plastic. Although in processing these compounds may give fewer problems than the bromine-containing flame retardants, for the most part they also have the disadvantage of adversely influencing the mechanical properties of the plastics.
The object of the present invention is to provide a plastic which, on the one hand, possesses flame-retarding properties by itself and can be used as such, and, on the other hand, can be conveniently blended with other plastics in the same manner as a flame retardant.